Retrieval of deleted voice messages in voice messaging system

ABSTRACT

Apparatus and method to allow retrieval of voice messages deleted from the voice message memory of a voice messaging system. A voice messaging system such as a telephone answering device includes a deleted voice message memory for storing voice messages deleted from the voice message memory. The deleted voice messages stored in the deleted voice message memory are retrievable by the user for review subject to rules for permanent deletion of the deleted voice messages (e.g., after a period of time, when the deleted voice message memory approaches capacity, periodically, etc.).

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation of co-pending application Ser. No. 12/489,812,filed on Jun. 23, 2009, which is a continuation of application Ser. No.09/296,538, filed on Apr. 22, 1999 and issued as U.S. Pat. No.7,558,381, the teachings of both of which are incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to a voice messaging system. Moreparticularly, it relates to a voice messaging system such as a telephoneanswering device which is capable of allowing a user to retrieve deletedmessages.

2. Background of Related Art

Voice messaging systems (e.g., telephone answering devices (TADs)) areuseful devices for both the home and office. Larger voice messagingsystems in general work in conjunction with a private branch exchange(PBX) unit to provide voice mailboxes for a large number of users.Smaller voice messaging systems, e.g., telephone answering devicestypically operate on a single telephone line and answer an incoming callto an unused (i.e., on-hook) telephone after a predetermined number ofrings.

Voice messaging systems and telephone answering devices cause atelephone line to enter an off-hook condition, then play an outgoinggreeting message to the caller. After the outgoing greeting message iscompleted, the caller is allowed to record a voice message on the voicemessaging system, e.g., telephone answering device. At a later time, thevoice message is replayed by the user, either local to the telephoneanswering device or via remote connection from another telephone throughthe public switched telephone network (PSTN).

FIG. 4 illustrates a conventional telephone answering device capable ofanswering an incoming call on a telephone line.

In FIG. 4, a telephone answering device 11 is connected to a telephonecompany central office 13 via a telephone line 15. A telephone lineinterface (TLI) 17 in the telephone answering device 11 provides theconventional isolation, DC and AC impedance as required by telephonecompany standards. The telephone line interface 17 also provides a ringdetect signal to a controller 19. The controller 19 can be any suitableprocessor, e.g., microprocessor, microcontroller, or digital signalprocessor (DSP). The ring detect signal indicates to the controller 19the ringing of an incoming call on the telephone line 15.

After a predetermined number of ring signals typically set at the voicemessaging system or telephone answering device, the telephone answeringdevice 11 causes the telephone line interface 17 to place the telephoneline in an off-hook state. A voice recorder/playback module 21 plays anoutgoing greeting message over the telephone line 15 to the caller. Uponcompletion of the outgoing greeting message, the caller may record avoice message in voice message memory 23 under the control of thecontroller 19 and through the voice recorder/playback module 21. Akeypad 25 allows the user to select various modes of operation,including the playback of voice messages, and the deletion of certainvoice messages.

In some instances, either before reviewing the voice message, during thereview of the voice message, or subsequent to reviewing the voicemessage, the user may either accidentally or intentionally delete aparticular voice message from the telephone answering device 11 thatthey later wish they hadn't deleted. While the conventional telephoneanswering device 11 allows a user to review recorded voice messages asmany times as desired before deletion, if a voice message is deleted,either accidentally or intentionally, the voice message is no longeraccessible for review by the user, and is erased from the voice messagememory 23.

Accordingly, there exists a need for an improved voice messaging systemand technique which allows a user to retrieve deleted voice messages.

SUMMARY OF THE INVENTION

In accordance with the principles of the present invention, a voicemessaging system comprises a telephone line interface, a controller, avoice message memory, and a deleted voice message memory. A voicemessage is initially stored in the voice message memory, and upondeletion of the voice message from said voice message memory, the voicemessage is stored in the deleted voice message memory.

A method for retrieving deleted voice messages from a voice messagingsystem in accordance with another aspect of the present inventioncomprises storing deleted voice messages in a deleted voice messagememory, and retrieving the deleted voice messages from the deleted voicemessage memory for playback.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the present invention will become apparent tothose skilled in the art from the following description with referenceto the drawings, in which:

FIG. 1 illustrates an embodiment of a voice messaging system, e.g., atelephone answering device capable of allowing a user to retrievedeleted voice messages from a deleted voice message memory, inaccordance with the principles of the present invention.

FIG. 2 is a flow chart illustrating an exemplary process by which a usercan retrieve a deleted voice message from the deleted voice messagememory of the telephone answering device shown in FIG. 1.

FIG. 3 is a flow chart illustrating an exemplary process by which a usercan permanently delete voice messages from the deleted voice messagememory of the telephone answering device shown in FIG. 1.

FIG. 4 illustrates a conventional telephone answering device capable ofrecording and deleting voice message with respect to voice messagememory.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The present invention provides a voice messaging system (e.g., atelephone answering device) and method which maintains deleted voicemessages and subsequently allows a user to retrieve deleted voicemessages from the telephone answering device.

In operation, a calling party would call a user who ultimately fails toanswer the telephone. After a predetermined number of rings, a telephoneanswering device in accordance with the principles of the presentinvention would automatically answer the telephone call by placing thetelephone line in an off-hook condition, and initiate a pre-recordedoutgoing greeting message. Thereafter, the calling party would record avoice message in voice message memory in the telephone answering deviceusing a voice recorder/playback module. After the voice message isrecorded, the calling party hangs up and is disconnected from thetelephone line and the telephone answering device. This recordingprocess may occur for a plurality of callers, to establish a pluralityof recorded voice messages.

In accordance with the principles of the present invention, a user ofthe telephone answering device can thereafter playback the recordedvoice messages and delete certain voice messages as desired. However, inaccordance with the principles of the present invention, upon deletion,a voice message is moved into a “trash can” memory area called a deletedvoice message memory for maintained storage until permanently deleted.

The retrieved, deleted voice messages may be played back directly fromthe deleted voice message memory, or may be recovered into anappropriate coding and/or format commensurate with undeleted voicemessages, and moved back to the voice message memory for playbacktherefrom.

In this way, a user is given a second opportunity to retrieve andplayback a particular voice message which they (or another user of thesame telephone answering device) deleted earlier.

For efficiency purposes, the voice messages moved to the deleted voicemessage memory may be more highly compressed than when they were storedin the voice message memory. To this end, a deleted voice message may bere-encoded and/or re-compressed by an appropriate program in thecontroller in the deletion process of movement from the voice messagememory to the deleted voice message memory.

Accordingly, if a deleted voice message is later desired for playback, auser may still be able to retrieve it for playback, subject to rules forpermanent deletion of the voice message from the deleted voice messagememory (e.g., after a period of time from initial deletion, on aperiodic basis, etc.), in accordance with the principles of the presentinvention.

Although the present invention is shown embodied in a telephoneanswering device, the present invention is equally applicable to voicemessaging systems in general, including voice mail systems.

FIG. 1 illustrates a telephone answering device, indicated generally at10, capable of recording voice messages from callers, and of allowing auser to retrieve and playback a deleted voice message memory, inaccordance with the principles of the present invention.

In particular, in the embodiment of FIG. 1, the telephone answeringdevice 10 includes at least one telephone line interface 12 forinterconnection with a telephone company central office 14 via atelephone line 16. The telephone line interface 12 interconnects thetelephone line 16 with a voice recorder/playback module 18.

The telephone answering device 10 further includes voice message memory28 where the voice recorder/playback module 18 initially stores recordedvoice messages, and deleted message memory 34 where the controller 24moves deleted voice messages from the voice message memory 28 upondeletion. Preferably, deleted voice messages stored in the deletedmessage memory 34 are maintained and thus not allowed to be overwrittenby other voice messages.

The user can, if desired, locally record an outgoing greeting messageinto the telephone answering device 10 through a microphone 26 connectedto the voice recorder/playback module 18. In operation, after a desirednumber of ring signals, the telephone answering device 10 causes thetelephone line interface 12 to place the telephone line 16 in anoff-hook state, and instructs the voice recorder/playback module 18 toplay an outgoing greeting message (e.g., stored in voice message memory28) on the telephone line 16 to the calling party.

Upon completion of the outgoing greeting message being played to thecalling party, the calling party can typically record a voice message inthe voice message memory 28 under the control of a controller 24 andthrough the voice recorder/playback module 18.

The voice message memory 28 is preferably formed in a non-volatilememory, e.g., Flash memory or ARAM, but can also be volatile memory insome applications. In the given example, a given amount of non-volatilememory (e.g., 16 Mb) is partitioned between the voice message memory 28and a deleted voice message memory 34. The capacity of each of the voicemessage memory 28 and/or the deleted voice message memory 34 can beadjusted to suit the needs of the particular application. Moreover, theprinciples of the present invention apply to voice message memory 28 anddeleted voice message memory 34 of any capacity.

Moreover, the capacity of each of the voice message memory 28 and/or thedeleted voice message memory 34 can be adjusted dynamically. Forinstance, when the voice message memory 28 passes a threshold amount ofuse indicating that it is filled to capacity with non-deleted voicemessages, a portion of the deleted voice message memory 34 can beallocated for use to store non-deleted voice messages. Then, when thevoice messages are deleted from the voice message memory 28, the size ofthe deleted voice message memory 34 can be enlarged as necessary tostore the deleted voice messages. In the preferred embodiment, the new,non-deleted voice messages have priority for storage over deleted voicemessages, so that if both the voice message memory 28 and the deletedvoice message memory 34 become filled to capacity, certain deleted voicemessages, e.g., the oldest, will be automatically deleted as necessaryto make room for storage of a newly recorded voice message, or messagesdeleted based on call related information (e.g., Caller ID information).

The telephone answering device 10 may further include a dual tonemultiple frequency (DTMF) generator 20 and/or a DTMF decoder 22implemented within or external to the controller 24. The DTMF generator20 provides touch tone signals for use by the telephone answering device10 to dial out on the telephone line 16 as directed by the user of thetelephone answering device 10. The DTMF decoder 22 provides aconventional mechanism for detection of DTMF commands input from aremote telephone via a touch tone keypad at a remote telephone.

The controller 24 controls the overall functions of the telephoneanswering device 10, including interpretation of commands from the user,including activation of keypad commands directing the playback and/ordeletion of recorded voice messages from a conventional keypad 30, andinterpretation of the directed retrieval of a deleted voice messageusing a retrieve deleted voice message button 73 or similar control. Theretrieve deleted voice message button 73 may cause the retrieval of allcurrently deleted voice messages maintained in the deleted voice messagememory 34, which is most appropriate if deleted voice messages arepermanently removed from the deleted voice message memory 34 on aregular basis. If deleted voice messages are allowed to build up in thedeleted voice message memory 34, it may be more desirable to implementthe retrieve deleted voice message button 73 to allow selection of aparticular deleted voice message. To this end, it may be desirable toinclude a display and scrolling control to allow review of currentlymaintained deleted voice messages for selection of only a particularlydesired deleted voice message. Alternatively, all voice messages may beplayed from deleted voice message memory 34, and when a RETRIEVE orsimilar button is activated, a particular voice message may be retrievedor moved from deleted voice message memory 34 back to the voice messagememory 28.

It is also within the principles of the present invention to provide acontrol mechanism (e.g., a manual “permanently delete” button) to allowthe user to bypass movement of a deleted voice message to the deletedvoice message memory 34, thereby causing permanent, irretrievabledeletion of the voice message.

The controller 24 may be any suitable processor, e.g. a microprocessor,a digital signal processor, or a microcontroller.

The keypad 30 allows the user to select various conventional modes ofoperation, including the playback of voice messages through a speaker 32connected to the voice recorder/playback module 18, and/or the initialdeletion of voice messages from the voice message memory 28.

Upon deletion of a voice message from the voice message memory 28 of thetelephone answering device 10, the deleted voice message is moved to thedeleted voice message memory 34 for maintained storage as a deletedvoice message, in accordance with the principles of the presentinvention.

It is within the scope of the present invention to increase the amountof effective capacity in the deleted voice message memory 34 bycompressing or re-compressing deleted voice messages using anappropriate low bit rate speech coder. Higher compression of deletedvoice messages with respect to undeleted voice messages allows arelatively larger number of voice messages to be stored in the deletedvoice message memory 34 as desired by the user.

FIG. 2 is a flow chart illustrating an exemplary process by which a usercan retrieve a deleted voice message from the deleted voice messagememory of the telephone answering device shown in FIG. 1.

In particular, with reference to FIG. 2, an incoming caller leaves avoice message on the telephone answering device 10 in step 202. After apredetermined number of rings, the telephone answering device 10 answersthe incoming call by causing the telephone line interface 12 to placethe telephone line 16 in an off-hook condition. The telephone answeringdevice 10 plays an outgoing greeting message such as “I'm not availableright now, please leave a message” or other similar greeting, and thecaller records a voice message for storage in the voice message memory28 of the telephone answering device 10.

In step 204, the user retrieves the voice message, either remotely orlocally, from the voice message memory 28.

In step 206, the user plays back as desired one or more recorded voicemessages stored in the voice message memory 28 of their telephoneanswering device 10.

In step 208, the user determines whether the played back voice messageis to be deleted from the voice message memory 28 of the telephoneanswering device 10. If the user does not desire to delete the voicemessage, the voice message remains stored in the voice message memory28, at least for a period of time, until the user deletes the voicemessage from the voice message memory 28 or until the telephoneanswering device otherwise automatically deletes the recorded voicemessage (e.g., after 30 days).

In step 210 the user causes the deletion of the voice message from thevoice message memory 28. Upon deletion of the voice message from thevoice message memory 28, the voice message is moved automatically by thetelephone answering device 10, either immediately or at an appropriatelater time when the telephone answering device is relatively inactive,to the deleted voice message memory 34.

Later, as shown in step 212, the user determines whether they want toretrieve a particular voice messages from the deleted voice messagememory 34.

As shown in step 214, if the user desires to retrieve a particulardeleted voice message stored in the deleted voice message memory 34,they simply activate the appropriate button and/or enter the appropriatecode into the telephone answering device 10 via the keypad 30, and thetelephone answering device 10 automatically retrieves the desireddeleted voice message from the deleted voice message memory 34.

In accordance with the principles of the present invention, there areseveral ways in which deletion of voice messages from the deleted voicemessage memory 34 can be accomplished by the user of the telephoneanswering device 10. For instance, the voice messages in the deletedvoice message memory 34 can be deleted manually, either individually oras a group, from the deleted voice message memory 34 by the user throughinput into the controller 24 via the keypad 30. For instance, at anydesired time and/or when the deleted voice message memory 34 becomesfull or about full, the user of the telephone answering device 10 maypermanently delete one or more of the deleted voice messages stored inthe deleted voice message memory 34 to allow additional voice messagesdeleted from the voice message memory 28 to be stored in the deletedvoice message memory 34.

Alternatively, the deleted voice messages maintained in the deletedvoice message memory 34 can be automatically deleted at certainpredetermined time intervals, e.g., every twenty-four (24) hours, once amonth, a period of time after the message was initially deleted, etc.

Yet another technique for permanently deleting deleted voice messagesfrom the deleted voice message memory 34 provides that when the numberof voice messages in the deleted voice message memory 34 exceeds apredetermined number of message as determined by the telephone answeringdevice 10 itself and/or the user.

Another technique for permanently deleting deleted voice messages in thedeleted voice message memory 34 can be automatically deleted when theutilized portion of the deleted voice message memory 34 reaches apredetermined capacity, e.g., ninety-percent full, etc.

In yet another technique, the deleted voice message memory 34 functionsas a first in, first out (FIFO) type device wherein the oldest storeddeleted voice messages is overwritten by the newest stored deleted voicemessage.

Finally, deleted voice messages can be permanently removed based on acomparison of associated call related information (e.g., Caller IDinformation) received with the original recording of the deleted voicemessage with, e.g., a specialized table of telephone numbers to bemaintained (all others deleted), a memory area such as that whichcontains the speed dial numbers for the particular voice messagingsystem.

FIG. 3 shows an exemplary process by which deleted voice messages may bepermanently deleted from the deleted voice message memory 34, inaccordance with the principles of the present invention.

In particular, with reference to FIG. 3, in step 302, the user of thetelephone answering device 10 initially deletes one or more voicemessages from the voice message memory 28 to the deleted voice messagememory 34.

As shown in decision step 304, the user determines whether any voicemessages stored in the deleted voice message memory 34 should bepermanently deleted from the deleted voice message memory 34.

If the user determines to delete any or all of the voice messages fromthe deleted voice message memory 34, in step 306, the user enters theappropriate manual command(s) into the controller 24 of the telephoneanswering device 10 via the keypad 30.

Thus, in accordance with the principles of the present invention, adeleted voice message from the voice message memory 28 of the telephoneanswering device 10 is maintained in deleted voice message memory 34 toallow retrieval of the deleted voice message subject to rulesestablished by the user for permanent deletion of deleted voicemessages. Thus, the user is capable of retrieving and playing back evenpreviously deleted voice messages, which is particularly useful in thecase of accidentally deleted voice messages which may be important tothe user. Furthermore, even intentionally deleted voice messages can beretrieved for playback by the user.

While the invention has been described with reference to the exemplaryembodiments thereof, those skilled in the art will be able to makevarious modifications to the described embodiments of the inventionwithout departing from the true spirit and scope of the invention.

What is claimed is:
 1. A voice messaging system, comprising: acontroller; a user accessible voice message memory to store at least oneuser accessible voice message; and a deleted voice message memory tostore at least one user deleted voice message; wherein: a first voicemessage is initially stored in said user accessible voice message memoryas a first user accessible voice message, and upon a user selecting akeypad option to delete said first user accessible voice message fromsaid user accessible voice message memory, said first user accessiblevoice message is automatically compressed, moved and restored in saiddeleted voice message memory as a first user deleted voice message, atotal storage space allocated to each of said user accessible voicemessage memory and said deleted voice message memory from a common totalmemory space is dynamically adjusted to re-allocate a space availablefor said user accessible voice message memory and said deleted voicemessage memory; said first user deleted voice message stored in saiddeleted voice message memory is removable from said deleted voicemessage memory to effect permanent deletion; and said first user deletedvoice message is removed from said deleted voice message memory uponreaching a predetermined percentage use of a memory capacity of saiddeleted voice message memory.
 2. The voice messaging system according toclaim 1, further comprising: a telephone line interface over which saidfirst voice message is initially received by said voice messagingsystem.
 3. The voice messaging system according to claim 1, wherein:said first user deleted voice message stored in said deleted voicemessage memory is retrievable for playback by a user.
 4. The voicemessaging system according to claim 1 wherein: said first user deletedvoice message is permanently deletable from said deleted voice messagememory via input from a keypad.
 5. The voice messaging system accordingto claim 1, wherein: said first user deleted voice message is removedfrom said deleted voice message memory and permanently deleted at apredetermined time interval.
 6. The voice messaging system according toclaim 1, wherein: said first user deleted voice message is removed fromsaid deleted voice message memory upon reaching a predetermined numberof voice messages being simultaneously stored in said deleted voicemessage memory.
 7. The voice messaging system according to claim 1,wherein: said first user deleted voice message stored in said deletedvoice message memory is compressed more than one or more other voicemessages stored in said user accessible voice message memory.
 8. Thevoice messaging system according to claim 1, wherein: said first userdeleted voice message in said deleted voice message memory is compressedusing a bit rate which is lower than a bit rate of one or more othervoice messages stored in said user accessible voice message memory.
 9. Amethod for managing a user deleted voice message from a voice messagingsystem, comprising: automatically removing said user deleted voicemessage stored in a user accessible first memory area upon a userselecting a keypad option to delete said user deleted voice message fromsaid user accessible first memory area, compressing said user deletedvoice message to produce a compressed user deleted voice message,storing said compressed user deleted voice message in a second memoryarea, dynamically adjusting a total storage space allocated to each ofsaid user accessible voice message memory and said deleted voice messagememory from a common total memory space to re-allocate a space availablefor said user accessible voice message memory and said deleted voicemessage memory, permanently deleting said compressed user deleted voicemessage by removing said compressed user deleted voice message stored insaid second memory area, and removing said compressed user deleted voicemessage from said second memory area upon reaching a predeterminedpercentage of a memory capacity of said second memory area.
 10. Themethod for managing a user deleted voice message from a voice messagingsystem according to claim 9, further comprising: retrieving saidcompressed user deleted voice message from said second memory area forplayback.
 11. The method for managing a user deleted voice message froma voice messaging system according to claim 9, further comprising:inputting a predetermined code via a keypad for retrieving saidcompressed user deleted voice message from said second memory area. 12.The method for managing a user deleted voice message from a voicemessaging system according to claim 9, wherein: said permanent deletionoccurs automatically based on a predetermined condition.
 13. The methodfor managing a user deleted voice message from a voice messaging systemaccording to claim 12, wherein: said predetermined condition correspondsto a length of time after said compressed user deleted voice message isstored in said second memory area.
 14. The method for managing a userdeleted voice message from a voice messaging system according to claim9, further comprising: removing said compressed user deleted voicemessage from said second memory area upon reaching a predeterminednumber of voice messages simultaneously stored in said second memoryarea.
 15. Apparatus for retrieving a user deleted voice message from avoice messaging system, comprising: means for automatically removingsaid user deleted voice message stored in a user accessible first memoryarea upon a user selecting a keypad option to delete said user deletedvoice message from said user accessible first memory area; means forcompressing said user deleted voice message to produce a compressed userdeleted voice message; means for storing said compressed user deletedvoice message in a deleted voice message memory; and means forretrieving said compressed user deleted voice message from said deletedvoice message memory for playback, means for dynamically adjusting atotal storage space allocated to each of said user accessible voicemessage memory and said deleted voice message memory from a common totalmemory space to re-allocate a space available for said user accessiblevoice message memory and said deleted voice message memory, and meansfor removing said compressed user deleted voice message from saiddeleted voice message memory upon reaching a predetermined percentage ofa memory capacity of said deleted voice message memory.
 16. Theapparatus for retrieving a user deleted voice message from a voicemessaging system according to claim 15, further comprising: means forinputting a predetermined code via a keypad for retrieving saidcompressed user deleted voice message from said deleted voice messagememory.
 17. The apparatus for retrieving a user deleted voice messagefrom a voice messaging system according to claim 15, further comprising:means for permanently deleting said voice message by removing saidcompressed user deleted voice message stored in said deleted voicemessage memory.
 18. The apparatus for retrieving a user deleted voicemessage from a voice messaging system according to claim 15, furthercomprising: means for removing said compressed user deleted voicemessage from said deleted voice message memory upon reaching apredetermined number of voice messages simultaneously stored in saiddeleted voice message memory.
 19. The voice messaging system accordingto claim 6, wherein: said user deleted voice message is an oldest storedvoice message in said deleted voice message memory.
 20. The method formanaging a user deleted voice message from a voice messaging systemaccording to claim 12, wherein: said predetermined condition correspondsto a predetermined time interval.
 21. A voice messaging system,comprising: a controller; a user accessible voice message memory tostore at least one user accessible voice message; and a deleted voicemessage memory to store at least one user deleted voice message;wherein: a first voice message is initially stored in said useraccessible voice message memory as a first user accessible voicemessage, and upon a user selecting a keypad option to delete said firstuser accessible voice message from said user accessible voice messagememory, said first user accessible voice message is automaticallycompressed, moved and restored in said deleted voice message memory as afirst user deleted voice message, a total storage space allocated toeach of said user accessible voice message memory and said deleted voicemessage memory from a common total memory space is dynamically adjustedto re-allocate a space available for said user accessible voice messagememory and said deleted voice message memory; said first user deletedvoice message stored in said deleted voice message memory is removablefrom said deleted voice message memory to effect permanent deletion; andsaid voice message is removed from said deleted voice message memoryupon reaching a predetermined number of voice messages beingsimultaneously stored in said deleted voice message memory.
 22. A methodfor managing a user deleted voice message from a voice messaging system,comprising: automatically removing said user deleted voice messagestored in a user accessible first memory area upon a user selecting akeypad option to delete said user deleted voice message from said useraccessible first memory area, compressing said user deleted voicemessage to produce a compressed user deleted voice message, storing saidcompressed user deleted voice message in a second memory area,dynamically adjusting a total storage space allocated to each of saiduser accessible voice message memory and said deleted voice messagememory from a common total memory space to re-allocate a space availablefor said user accessible voice message memory and said deleted voicemessage memory, permanently deleting said compressed user deleted voicemessage by removing said compressed user deleted voice message stored insaid second memory area, and removing said compressed user deleted voicemessage from said second memory area upon reaching a predeterminednumber of voice messages simultaneously stored in said second memoryarea.
 23. Apparatus for retrieving a user deleted voice message from avoice messaging system, comprising: means for automatically removingsaid user deleted voice message stored in a user accessible first memoryarea upon a user selecting a keypad option to delete said user deletedvoice message from said user accessible first memory area; means forcompressing said user deleted voice message to produce a compressed userdeleted voice message; means for storing said compressed user deletedvoice message in a deleted voice message memory; and means forretrieving said compressed user deleted voice message from said deletedvoice message memory for playback, means for dynamically adjusting atotal storage space allocated to each of said user accessible voicemessage memory and said deleted voice message memory from a common totalmemory space to re-allocate a space available for said user accessiblevoice message memory and said deleted voice message memory, and meansfor removing said compressed user deleted voice message from saiddeleted voice message memory upon reaching a predetermined number ofvoice messages simultaneously stored in said deleted voice messagememory.